This invention relates to service shut off devices and more particularly to articles known as fire collars.
Service shut off devices or fire collars are placed around service lines such as plastics materials pipes or cable trays where they pass through a wall or soffit so that in the event of a fire intumescent material within the service shut off devices or fire collars will expand and close off the hole through the wall or soffit to prevent the fire passing from one part of a building to another.
Service shut off devices or fire collars are generally made for a single size of pipe or cable tray or other service line and therefore where a major installation is occurring and there may be a number of different sizes and shapes of plastic pipes, cable trays or other service lines then a large stock of service shut off devices or fire collars is necessary.
It is the object of this invention to provide a service shut off device or fire collar arrangement where a large range of different size and shape stocks is not necessary.
In one form, therefore, the invention is said to reside in a service shut off device comprising a selected length of a composite body adapted to be formed into a shape to fit in use around a service line, the composite body having a flexible casing and a body of intumescent material received in the casing, the composite body further comprising means associated with the casing to contain the intumescent material within the casing and means to retain the collar in a selected shape around the service line.
Preferably the body of intumescent material is continuous. The body of intumescent material may be transversely cut or perforated at intervals to assist with selection of the required length of the service shut off device.
It will be seen that by this means a selected length of a strip of service shut off device or fire collar material can be wrapped around a cable tray, service line or a pipe or formed into selected shape to be placed around a cable tray, service line or a pipe and retained in that shape.
In one preferred embodiment of the invention the flexible casing may be substantially U-shaped with the intumescent material received in the hollow of the U-shape.
Alternatively the casing may only provide a backing for the intumescent material or may provide a backing and one edge.
Preferably the casing may be made from a metallic material such as sheet aluminium, stainless steel or steel and may be anodised or galvanised to prevent corrosion in an installation. The casing may comprise a perforated metal sheeting which is flexible enough to be bent into the required shape.
Alternatively the casing may be manufactured from a composite material such as a glass reinforced material or the like.
The flexibility of the casing may be provided by a plurality of transverse lines of weakening in the casing and the intumescent material being sufficiently flexible to be able to be bent around the service line or pipe or containing areas of weakening to enable it to be bent into a selected shape such as a circular shape.
The means to retain the collar in the selected shape such as a circular shape may be a wire or other strap material which can be wound around the collar when it is formed into the selected shape and joined to hold the collar in that shape. Alternatively fasteners such as screws or blind rivets may be used to hold the device in the selected shape.
In one embodiment the service shut off device or fire collar may be adapted to be formed around a service line within a wall or soffit or alternatively the service shut off device or fire collar may be mounted against a wall or soffit.
There may be provided brackets either associated with the casing or a separate bracket which can be fastened onto the casing to hold the casing against a wall or soffit.
There may be tabs extending from the casing which may provide the brackets.
There may be a plurality of co-acting connecting pieces on the bracket and the casing so that the racket is retained onto the casing.
The co-acting connecting piece between the casing and the bracket may also act to be a connector between the ends of the casing of the composite body to both retain the casing in the selected shape and to be used as a bracket. Hence the bracket both holds the selected shape of the fire collar and acts as a mounting bracket.
The means associated with the casing to contain the intumescent material within the casing may be an adhesive. Alternatively it may include a plurality of tabs associated with the casing which extend against or into the intumescent material.
The means to retain the collar in the selected shape may include a link member, the link member having a plurality of pins adapted to co-act with apertures on the casing across a join in the casing whereby the collar is retained in the selected shape.
The service shut off device may include a plurality of co-acting connecting pieces on the bracket and the casing so that the bracket is retained onto the casing.
The service shut off device may be provided by a stack of more than one service shut off device as discussed above.
In an alternative form the invention is said to reside in a continuous strip fire collar material including a casing and a continuous flexible intumescent material within the casing, the strip comprising the casing and intumescent material adapted to be severed at selected intervals along the length of the continuous strip such that the strip can be cut off at the selected length and the severed portion wrapped around a service line such as a pipe or cable tray to provide a fire collar.
The casing may be sufficiently flexible to enable it to be formed into the selected shape or the casing may be provided with transverse lines of weakening at intervals along its length so that it may be wrapped into a selected shape of a fire collar.
The transverse points of weakening may be done by a plurality of perforations transverse to the length of the strip, or alternatively may be done by thinning of the material in transverse lines across the strip material.
Such transverse lines of weakening may also provide the regions at which the strip of material can be severed to form the individual lengths for the fire collar and also enable it to be bent around or wrapped around to form a selected shape for the fire collar.
The casing may include lugs formed or bent out of the plane of the casing to extend onto or into the intumescent material within the casing to retain the intumescent material in the casing.
The casing may also include tabs extending from the casing which may be bent out to provide brackets to mount the service shut off device to a wall or soffit.
In one preferred embodiment the casing may be comprised of a face section and two side sections adapted in use to provide a substantially U-shaped body. The lugs bent out of the casing may be on the face of the casing or on one of the side sections.
Alternatively the casing may only provide a backing for the intumescent material or may provide a backing and one edge.
Preferably the side sections are formed from a plurality of tabs configured such that upon bending of the continuous strip into a selected shape such as a circular shape the tabs enable the inner side of the strip to form a smaller radius than the outer side. The tabs may overlap or pass under adjacent tabs to enable the bending. One method by which this can be done is to provide two bend lines between the face section and each side section with the lines separated by essentially the thickness of the casing material. Alternate tabs may be bent on one line and the in between tabs bent on the other line. Alternatively a bend line for each tab may be angled to the direction of elongation of the strip so that during bending a tab passes under the adjacent tab on one side and over the adjacent tab on its other side.
There may be further provided from one or both of the side sections tongues extending from the side sections and which are folded over the intumescent material such that they are substantially parallel to the face. One tongue may extend from each tab on each side. Such tongues may assist in retaining the intumescent material within the casing and to assist with crushing of a pipe when the intumescent material is expanding in use or to assist with transfer of heat to the pipe so that it assists with softening of the pipe.
There may be further provided brackets to mount the fire collar to a wall or ceiling or soffit in use.
The brackets may be adapted to clip onto the casing so that they are attained with the casing.
In one preferred embodiment of the invention there may be provided a plurality of co-acting connecting portions on the brackets and collar so that the bracket can be retained onto the collar. In one form the co-acting connecting arrangement may be a plurality of slots formed in the casing with a plurality of pins on the brackets. Alternatively the pins may be provided on the casing and the slots on the brackets.
There may be further provided means to retain the continuous strip of material into a selected shape such as a circular shape. Such a means may be comprised of wire or other strip material adapted to be wrapped around the casing and joined together to form the selected shape of the fire collar.
Alternatively the joining of the continuous strip into the selected shape may be done by the brackets being mounted by the co-acting connecting portions on both ends of the strip when wrapped in the selected shape so that the bracket acts as both the mounting bracket and retainer for the selected shape. In such an embodiment the bracket may include at least two pairs of co-acting connecting catch means so that the casing can be gripped across the joint.
The intumescent material may be retained onto the casing by an adhesive.
It will be seen that generally from this invention by having a continuous strip of fire collar material the strip can be broken off or severed in a selected length and then wrapped around a service line such as a cable tray or pipe. Hence a tradesman need only carry a continuous length of the material onto site and the material cut off to length as required.
The continuous strip of the present invention may be transported in a packaging system for a continuous strip material type of the type discussed above which is adapted to be used in a selected length, the packaging comprising a cuboidal body adapted to contain a roll of the continuous strip material, the cuboidal body having two opposed sides and two pairs of opposed edges, a slot in a first edge of the cuboidal body through which the material may be drawn and markings on the packaging on or adjacent the first edge to enable measurement of the selected length.
It will be seen that by use of such a packaging system a continuous strip such as the continuous strip of fire collar material may be stored within the packaging and the strip drawn out just to the length required then the strip broken off or severed off by other means to give the strip of material which can be formed into the fire collar.
The packaging system may also include a drawer or other receptacle within the body which can hold the brackets or other means for retaining the fire collar into a circular shape.
The packaging system may also have an axis formed into it from one face to the other so the roll of strip material is supported while it is being unwound or alternatively shaping of packing within the packaging may assist to retain the roll of strip material in a substantially wound form.
There may be slot in one of the faces so that a user may view the strip within the casing to see what length of the strip is still remaining.
In a further form the invention may be said to reside in an intumescent material for a service shut off device, the intumescent material including a plurality of voids such that a strip of the material can be formed into substantially circular shape with the material being compressed and absorbing the compression by means of the voids to allow for an inner circumference which is smaller than an outer circumference.
Preferably the intumescent material has a backing material which is a non woven fibrous material and the non woven fibrous material is severed transversely at intervals to provide lines of weakening for cutting of the strip to a required length.
In a further form the invention may be said to reside in a service shut off device comprising a stack of two or more fire collars.
By this arrangement there can be obtained a faster shut off or a more powerful shut off of a service line such as a pipe.
This then generally describes the invention but to assist with understanding, reference will now be made to the accompanying drawings which show a preferred embodiment of the invention.